INDIANAPOLIS — Hospitals across Indiana are tightening visitor restrictions in hopes of preventing the spread of flu, which has claimed the lives of 27 people in the state this season.

Indianapolis health officials have asked area hospitals to implement a policy developed in 2009 during the H1N1 pandemic. It prohibits people with flu-like illnesses from visiting hospital patients. Additionally, visits are restricted to immediate family, partners and significant others. All visitors under 18 must make special arrangements to see a patient. Hospitals in Munster and Evansville are adopting similar policies during the outbreak, according to local news reports.

In 2009, such restrictions were in place for about two months in Marion County.

"This policy is a proven approach to reduce the spread of flu," said Charles Miramonti, chairman of the Indianapolis Coalition for Patient Safety. "You have to move early for something like this."

The spread of flu in the area has not yet reached critical levels, but the illness is still on the rise, said Virginia Caine, director of the Marion County Public Health Department.

The new visitation policy goes into effect for Marion County hospitals on Friday. Employees at hospital welcoming desks will ask visitors if they are sick, and instruct them to visit at another time if they meet criteria the policy mentions.

State health department spokesman Ken Severson said the agency is still urging Indiana residents to get flu shots because it's not too late to benefit from the vaccine's protections.

"There are ample supplies of the vaccine around the state," he said.

Health officials say it takes about two weeks for the vaccine's full protection to kick in. The vaccines are especially recommended for older people, young children and anyone with medical conditions such as heart or lung diseases that put them at high risk of dangerous flu complications.

The state's ongoing flu outbreak has claimed 27 lives, with 17 of those deaths reported during the past week. Nine of those who died had received flu vaccine shots.

Wednesday's flu update from the State Department of Health says 20 of the people who have died in Indiana had underlying medical conditions such as heart disease.

In Vincennes, local pharmacies are running out of the antiviral medication Tamiflu, which is used to slow or stop flu symptoms, the Sun Commercial reported.

The vaccine for the illness is still available across the state. The Marion County health department will hold a free flu shot clinic on Friday from 1 to 5 p.m. at the training center at 4012 N. Rural St. Those younger than 18 must be accompanied by a parent or guardian.